Graves' disease in HTLV-I carriers

Human T-cell leukemia virus type 1 is associated with dysthyroidism in the French Amazon

Background

Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus known to cause two major diseases: adult T-cell leukemia/lymphoma and a progressive neuromyelopathy-tropical spastic paraparesis. Many viruses may be involved in the pathogenesis of thyroiditis; however, few studies have focused on the role of HTLV-1. We aimed to investigate the association between HTLV-1 and biological thyroid dysfunction.

Methods

We included 357 patients with a positive HTLV-1 serology and thyroid-stimulating hormone assay data between 2012 and 2021 in a hospital in French Guiana; we compared the prevalence of hypothyroidism and hyperthyroidism in this group with that in an HTLV-1-negative control group (722 persons) matched for sex and age.

Results

The prevalence of hypothyroidism and hyperthyroidism in patients with HTLV-1 infection was significantly higher than that in the control group (11% versus 3.2% and 11.3% versus 2.3%, respectively; p < 0.001).

Conclusion

Our study shows, for the first time, the association between HTLV-1 and dysthyroidism in a large sample, suggesting that thyroid function exploration should be systematically implemented in this population as this may have an impact on therapeutic management.

Systemic diseases in patients with HTLV-1-associated uveitis

BACKGROUND

Human T-lymphotropic virus type 1 (HTLV-1) carriers may develop severe systemic diseases, such as adult T cell leukaemia (ATL) or HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). This study aims to investigate systemic diseases of HTLV-1 carriers who had developed HTLV-1-associated uveitis (HAU).

METHODS

We investigated the occurrence of systemic diseases in 200 patients with HAU by performing a retrospective investigation of their medical records and examining the results of a postal survey.

RESULTS

The mean age of HAU onset was 49 years, and the total person-years from HAU onset was 1627. There were two cases of ATL. Of these, one was diagnosed with smouldering ATL at the time of HAU onset and the other developed acute-type ATL 4 years after HAU onset. There were 26 cases of HAM/TSP; of these, HAM/TSP occurred first in 13 cases and HAU occurred first in 11 cases. The interval between the onset of HAM/TSP and HAU ranged from 6 months to 6 years, with no significant difference observed based on whether HAM/TSP or HAU occurred first. Hyperthyroidism was noted in 45 cases and preceded onset in all cases. HAU onset occurred after starting thiamazole treatment, and in two cases HAU recurred each time thiamazole treatment was restarted.

CONCLUSION

HTLV-1 carriers with HAU may develop HAM/TSP more frequently than general carriers. HTLV-1 carriers undergoing treatment for hyperthyroidism may be prone to developing HAU.

Association Between Non-Infectious Uveitis and Thyroid Dysfunction: A Case Control Study

BACKGROUND

Several reports suggested a relation between uveitis and thyroid disease or dysfunction. However, no study has investigated the association between uveitis and thyroid dysfunction. The purpose of this study was to compare the prevalence of thyroid dysfunction in patients with and without non-infectious uveitis.

METHODS

This was a retrospective, case-control study.

RESULTS

Two hundred thirty-five non-infectious uveitis patients (uveitis group) and 600 controls (control group) were included in the study, of whom 492 (58.9%) were females. No differences were demonstrated between the uveitis and control groups with regard to baseline characteristics, including age, sex, and the presence of systemic diseases such as diabetes, hypertension, and cardiac disease. Rheumatologic and gastrointestinal disease were more common in the uveitis group (p < 0.001 and p = 0.007, respectively). Overall, thyroid dysfunction was noted in 61 (7.3%) patients, of whom 55 had hypothyroidism and six had hyperthyroidism. Seventeen out of 235 (7.2%) uveitis patients and 44/600 (7.3%) controls were diagnosed with thyroid dysfunction-a similar proportion in both groups (p = 0.96). Of these, all uveitis patients and 38 (86.4%) patients in the control group had a diagnosis of hypothyroidism (p = 0.63). A higher percentage of women was found among uveitis patients with thyroid dysfunction compared with uveitis patients without thyroid dysfunction (p = 0.002). The most common uveitis type was anterior uveitis. No significant difference was found in uveitis types between patients with or without a diagnosis of thyroid dysfunction.

CONCLUSIONS

The prevalence of thyroid dysfunction was similar in both groups, and no association was found between non-infectious uveitis and thyroid dysfunction in this study. These findings suggest there is no need for routine thyroid function evaluation in patients with non-infectious uveitis.

Inflammatory manifestations of HTLV-1 and their therapeutic options

Human T lymphotropic virus type 1 (HTLV-1) is one of the most intriguing retroviruses infecting humans. Most commonly, infection remains undetected, since it does not cause obvious harm, yet in 4-9% of patients, this infection can be devastating, causing adult T-cell leukemia/lymphoma and/or HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). This review concentrates on all inflammatory aspects of HTLV-1 infection: HAM/TSP, HTLV-1 associated uveitis, HTLV-1 associated conjunctivitis, sicca syndrome and interstitial keratitis, HTLV-1 associated Sjögren's syndrome, Hashimoto's thyroiditis and Graves' disease, HTLV-1 associated pulmonary disease, infective dermatitis associated with HTLV-1, HTLV-1 associated inflammatory myositis and HTLV-1 associated arthritis. With the exception of HAM/TSP treatment, studies of these conditions are sparse and even for HAM/TSP, the level of evidence is limited. While control or elimination of infection remains a goal, most therapy beyond symptomatic management is directed at the immune response to HTLV-1.

Viruses and thyroiditis: an update

Viral infections are frequently cited as a major environmental factor involved in subacute thyroiditis and autoimmune thyroid diseases This review examines the data related to the role of viruses in the development of thyroiditis.

Our research has been focused on human data. We have reviewed virological data for each type of thyroiditis at different levels of evidence; epidemiological data, serological data or research on circulating viruses, direct evidence of thyroid tissue infection. Interpretation of epidemiological and serological data must be cautious as they don't prove that this pathogen is responsible for the disease. However, direct evidence of the presence of viruses or their components in the organ are available for retroviruses (HFV) and mumps in subacute thyroiditis, for retroviruses (HTLV-1, HFV, HIV and SV40) in Graves's disease and for HTLV-1, enterovirus, rubella, mumps virus, HSV, EBV and parvovirus in Hashimoto's thyroiditis. However, it remains to determine whether they are responsible for thyroid diseases or whether they are just innocent bystanders. Further studies are needed to clarify the relationship between viruses and thyroid diseases, in order to develop new strategies for prevention and/or treatment.

Myasthenia gravis associated with HTLV-I infection and atypical brain lesions

We report a patient who experienced progressive diplopia and distal weakness of the upper limbs. Magnetic resonance imaging of the brain showed extensive white matter lesions and analysis of cerebrospinal fluid revealed acute human T-lymphotropic virus type I (HTLV-I) infection. Myasthenia gravis (MG) was evidenced by electromyography (EMG) and antibodies against acetylcholine receptor. This unusual case of MG associated with HTLV-I infection and brain-restricted lesions underscores the possible link between viruses and MG pathogenesis.

Severe graves ophthalmopathy accompanied by HTLV-1-associated uveitis (HAU) and anti-neutrophil cytoplasmic antibody-related vasculitis: a case report and a review of the literature of HAU with Graves disease

A 50-year-old woman was admitted because of severe exophthalmos associated with Graves disease. She underwent methimazole (MMI) and methylprednisolone pulse therapy against exophthalmos. She noticed photophobia and blurred vision 3 weeks after the start of pulse therapy and she was diagnosed as having uveitis. Methylprednisolone pulse therapy was performed again for both exophthalmos and uveitis, followed by daily administration of 20 mg of prednisolone and instillation of betamethasone for 2 weeks and the uveitis was improved. Western blot analysis confirmed that human T lymphotropic virus type 1 (HTLV-1) antibody was present in her serum. Propylthiouracil was substituted for MMI and HTLV-1-associated uveitis (HAU) has not recurred. Six months after the beginning of administration of PTU, anti-neutrophil cytoplasmic antibody-related vasculitis developed in the patient. We review 43 cases of HAU with Graves disease, including the present case, in the literature. Only 2 of 27 cases (except unknown cases) (7.4%) had Graves ophthalmopathy. To the best of our knowledge, there has been no investigation of HAU and Graves ophthalmopathy.

High frequencies of human T-lymphotropic virus type I (HTLV-I) infection and presence of HTLV-II proviral DNA in blood donors with anti-thyroid antibodies

To investigate the relationship between human T-lymphotropic virus (HTLV) types I and II and the pathogenesis of autoimmune thyroid diseases, we examined serum anti-thyroid antibodies in 1019 blood donors with or without serum anti-HTLV-I antibody as well as proviral DNA for HTLV-II in leukocyte DNA by the polymerase chain reaction in 395 blood donors with or without anti-thyroid antibodies. The frequency of donors with anti-HTLV-I antibody who also showed anti-thyroid antibodies (7.9%) tended to be higher than that (6.3%) among donors who did not have the anti-HTLV-I antibody. The frequency of anti-thyroid antibodies in 125 young male donors aged 16-39 years with anti-HTLV-I antibody (4.8%) was significantly higher (P < 0.05) than that (0.6%) in 164 control donors without the antibody. In blood donors with anti-thyroid antibody, 25.0% of those with anti-HTLV-I antibody and 14.3% of those without the antibody had HTLV-II proviral DNA. In contrast, in donors without anti-thyroid antibody HTLV-II proviral DNA was detected in 2.3% of those with anti-HTLV-I antibody and in 0.6% of those without the antibody. Thus the detection rates in donors with anti-thyroid antibody were significantly higher (P < 0.001) than those in donors without the antibody, regardless of HTLV-I infection. These results suggest that HTLV-I infection and the presence of HTLV-II proviral DNA may be independently related to the pathogenesis of autoimmune thyroid diseases.